The objective for this Small Grant Application is to test the hypothesis, "angiogenisis and epithelialization in periodontal wounds are mediated by membrane-type matrix metalloproteinase-1 (MT-MMP-1) and gelatinase A in a time and tissue specific manner." It has three Aims. In Aim 1, an in vitro gingival wound healing model will be established using surgical specimens of human gingiva. The specimens will be obtained from routine graft procedures, second stage implant or periodontal flap surgeries, cored, and epithelium removed to generate a 3-mm wound. The wounded tissue will be cultured for 0, 3 5 and 7 days and processed for histology, immuohistochemistry and Western blotting. Culture medium will be examined by zymography. In Aim 2, cryosections will be subjected to histology and immunofluorescence with several chosen antibodies. The extent of reepithelialization will be quantified by histology, and proliferative activity of keratinocytes measured by BrdU uptake. In Aim 3 expression of MT-MMP-1 and gelatinase A will be examined by immunofluorescence with anti-MT-MMP-1 and MMP-2 antibodies, Western analysis of wound extracts, and gelatin zymography of culture medium.